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The relationship between the average structure of the inner magnetospheric large-scale electric field and geomagnetic activity levels has been investigated by Double Star TC-1 data for radial distances &rho; between 4.5 <I>R</I>_E and 12.5 <I>R</I>_E and MLT between 18:00 h and 06:00 h from July to October in 2004 and 2005. The sunward component of the electric field decreases monotonically as &rho; increases and approaches zero as the distance off the Earth is greater than 10 <I>R</I>_E. The dawn-dusk component is always duskward. It decreases at about 6 <I>R</I>_E where the ring current is typically observed to be the strongest and shows strong asymmetry with respect to the magnetic local time. Surprisingly, the average electric field obtained from TC-1 for low activity is almost comparable to that observed during moderate activity, which is always duskward at the magnetotail (8 <I>R</I>_E~12 <I>R</I>_E).